Figure 2.

Evolutionary relationships of UCP1-3 family members. We have reconstructed a phylogeny
using a total of 161 protein sequences of UCP1-4 retrieved from GenBank, and aligned
using Mafft v. 6.626 with the L-INS-i strategy. A final alignment of 281 positions
was obtained after removing ambiguous positions using Gblocks v.0.91b. The JTT+I+G
was selected as the best-fit evolutionary model using Prottest v. 2.0. The maximum
likelihood tree (-lnL = 15417.6) was inferred using PhyML v. 2.4.4 with midpoint rooting.
An approximately unbiased test performed using RaxMLv. 7.0.4 and Consel v. 0.1 determined
that the constrained tree (-lnL = 15433.2) shown in the figure was not significantly
different (P > 0.05) and, thus, within the confidence set. Bootstrap analysis was performed using
RaxML at the Cipres Portal, and bootstrap values for relevant nodes are shown in the
tree. Taxonomic groups are represented by different colors. Inset: phylogeny of mitochondrial
carrier proteins adapted from [6]. Our reconstructed phylogeny shows animal UCP4 and UCP5 (also termed BMCP1) as a
sister group of plant UCPs and animal UCP1-3. The other members of the superfamily
analyzed – PiC, ANT, OGC (oxoglutarate carrier) and DIC (dicarboxylate carrier) –
were found to be more distantly related paralogs.